Thread: Vista photocell

I have a client that has a vista lighting setup that would always be on when plugged even though it has photocell. I even tried shining a flash light onto it to shut it off, but it would not. I replaced the photocell and wired it the same as the original photocell, which is the same as the vista diagram. 120v going into the photocell, and then going to the transformer. The lights worked for one minute and then shutoff and would not turn back on even with tape over the cell. When I bypass the wiring for the photocell everthything works. Any Ideas?
Thanks

I am not a huge fan of photocells for a few different reasons, but they are out there and so you have to learn to deal with them. I would suggest two things when trying to diagnose them.

1: When covering the photocell during daylight hours in order to test them, be diligent. You generally need to use more than one layer of tape and ensure the edges of the cell are taped off too. You would think that a small strip of tape over the cell would be enough, but it rarely is.

2: Be patient. I have found that some cells have a long 'lag' between off and on. In some cases up to a couple of minutes spent waiting for the photocell to respond to dark.

Ultimately, take the opportunity to offer the client an upgrade to a digital astronomic timer!